<template>
    <div class="component-upload-image">
        <el-upload multiple :action="uploadImgUrl" list-type="picture-card" :on-success="handleUploadSuccess"
            :before-upload="handleBeforeUpload" :limit="limit" :on-error="handleUploadError" :on-exceed="handleExceed"
            name="file" :on-remove="handleRemove" :show-file-list="true" :headers="headers" :file-list="fileList"
            :on-preview="handlePictureCardPreview" :class="{ hide: this.fileList.length >= this.limit }">
            <i class="el-icon-plus"></i>
        </el-upload>

        <!-- 上传提示 -->
        <div class="el-upload__tip" slot="tip" v-if="showTip">
            请上传
            <template v-if="fileSize"> 大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b> </template>
            <template v-if="fileType"> 格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b> </template>
            的文件
        </div>

        <el-dialog :visible.sync="dialogVisible" title="预览" width="800" append-to-body>
            <img :src="`${url}${dialogImageUrl}`" style="display: block; max-width: 100%; margin: 0 auto" />
        </el-dialog>
    </div>
</template>

<script>

import {getToken} from '@/utils/storage.js'
export default {
    props: {
        value: [String, Object, Array],
        // 图片数量限制
        limit: {
            type: Number,
            default: 5,
        },
        // 大小限制(MB)
        fileSize: {
            type: Number,
            default: 5,
        },
        // 文件类型, 例如['png', 'jpg', 'jpeg']
        fileType: {
            type: Array,
            default: () => ["png", "jpg", "jpeg"],
        },
        // 是否显示提示
        isShowTip: {
            type: Boolean,
            default: true
        }
    },
    data() {
        return {
            number: 0,
            uploadList: [],
            dialogImageUrl: "",
            dialogVisible: false,
            hideUpload: false,
            url:process.env.VUE_APP_BASE_API,
            uploadImgUrl:process.env.VUE_APP_BASE_API +'/prod-api'+ "/file/upload", // 上传的图片服务器地址
            headers: {
                    Authorization: "Bearer " + getToken(),
            },
            fileList: []
        };
    },
    watch: {
        value: {
            handler(val) {
                if (val) {
                    // 首先将值转为数组
                    const list = Array.isArray(val) ? val : this.value.split(',');
                    // 然后将数组转为对象数组
                    this.fileList = list.map(item => {
                        if (typeof item === "string") {
                            item = { name: item, url: item };
                        }
                        return item;
                    });
                } else {
                    this.fileList = [];
                    return [];
                }
            },
            deep: true,
            immediate: true
        }
    },
    computed: {
        // 是否显示提示
        showTip() {
            return this.isShowTip && (this.fileType || this.fileSize);
        },
    },
    methods: {
        // 删除图片
        handleRemove(file, fileList) {
            const findex = this.fileList.map(f => f.name).indexOf(file.name);
            if (findex > -1) {
                this.fileList.splice(findex, 1);
                this.$emit("input", this.listToString(this.fileList));
            }
        },
        // 上传成功回调
        handleUploadSuccess(res) {
            this.uploadList.push({ name: res.data.url, url: res.data.url });
            if (this.uploadList.length === this.number) {
                this.fileList = this.fileList.concat(this.uploadList);
                this.uploadList = [];
                this.number = 0;
                this.$emit("input", this.listToString(this.fileList));
                // this.$modal.closeLoading();
            }
        },
        // 上传前loading加载
        handleBeforeUpload(file) {
            let isImg = false;
            if (this.fileType.length) {
                let fileExtension = "";
                if (file.name.lastIndexOf(".") > -1) {
                    fileExtension = file.name.slice(file.name.lastIndexOf(".") + 1);
                }
                isImg = this.fileType.some(type => {
                    if (file.type.indexOf(type) > -1) return true;
                    if (fileExtension && fileExtension.indexOf(type) > -1) return true;
                    return false;
                });
            } else {
                isImg = file.type.indexOf("image") > -1;
            }

            if (!isImg) {
                this.$message.error(`文件格式不正确, 请上传${this.fileType.join("/")}图片格式文件!`);
                return false;
            }
            if (this.fileSize) {
                const isLt = file.size / 1024 / 1024 < this.fileSize;
                if (!isLt) {
                    this.$message.error(`上传头像图片大小不能超过 ${this.fileSize} MB!`);
                    return false;
                }
            }
            this.$message.warning("正在上传图片，请稍候...");
            this.number++;
        },
        // 文件个数超出
        handleExceed() {
            this.$message.error(`上传文件数量不能超过 ${this.limit} 个!`);
        },
        // 上传失败
        handleUploadError() {
            this.$message.error("上传图片失败，请重试");
            // this.$modal.closeLoading();
        },
        // 预览
        handlePictureCardPreview(file) {
            this.dialogImageUrl = file.url;
            this.dialogVisible = true;
        },
        // 对象转成指定字符串分隔
        listToString(list, separator) {
            let strs = "";
            separator = separator || ",";
            for (let i in list) {
                strs += list[i].url + separator;
            }
            return strs != '' ? strs.substr(0, strs.length - 1) : '';
        }
    }
};
</script>
<style scoped lang="scss">
// .el-upload--picture-card 控制加号部分
::v-deep.hide .el-upload--picture-card {
    display: none;
}

// 去掉动画效果
::v-deep .el-list-enter-active,
::v-deep .el-list-leave-active {
    transition: all 0s;
}

::v-deep .el-list-enter,
.el-list-leave-active {
    opacity: 0;
    transform: translateY(0);
}
</style>

